Electromechanical brakes differ from the hydraulic or pneumatic brakes widely used in the motor vehicle field in that the brake application force is not generated hydraulically or pneumatically but by electromechanical means.
The first generation of electromechanical motor vehicle brakes attempted to produce the considerable brake application force necessary by means of an electric motor on each wheel brake, generally with a downstream reduction gear mechanism, in order to limit the size and therefore the weight of the electric motor. However, the in some cases very high reduction ratios selected in the order of 1:200 greatly impaired the dynamic behavior of the brake, which made such solutions appear unsatisfactory overall. Consequently, solutions of this kind have as yet never gone into commercial production.
Electromechanical brakes with self-energization are much more promising, as this type of electromechanical brake only requires a relatively small electric actuator and derives most of the brake application force from the kinetic energy of the moving brake element to be decelerated, e.g. from a brake disk as it rotates during vehicle operation. The basic operating principle of such electromechanical brakes with self-energization is described in German patent 198 19 654. However, because of this operating principle, high brake application forces can only be achieved when a vehicle in which such an electromechanical brake with self-energization is installed is moving.